The pondskater Gerris lateralis in the Netherlands: wing polymorphism, identification, biology and distribution (Heteroptera: Gerridae) In the Netherlands the pondskater Gerris lateralis is a rare species with a limited distribution. Moreover, a substantial number of records concern macropterous specimens, considered as migrants. Recent findings, however, indicate that the species is more common than suspected, mainly because of its hidden way of life in less accessible habitats such as swamps. The relatively young population discovered in the recently reclaimed polder Zuid-Flevoland showed a high frequency of the macropterous morph in comparison to the almost completely apterous populations on the ‘old land’. The current observations support the assumption that wing dimorphism in Gerris lateralis is genetically determined with dominancy of the apterous morph. The macropterous morph obviously is common enough to establish new populations.